mandlmaunder
regular
Reged: 11/07/2007
Posts: 672
Loc: US Virgin Islands, for the mo
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If you have a keyway(spline or woodruff key) you can make a flat plate with a hole of the correct shaft and spline fit , machine or by some less technical method produce a flat spot on your cone then bend the protruding piece of flat plate so it can't slip or rotate.
sounds complicated but isn't.
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Youth is wasted on the young
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skipper_stu
regular
Reged: 24/02/2003
Posts: 2545
Loc: North Wales
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I cannot believe I am reading this, if you dont understand the engineering theory of a tapered, keyed, fixing method then you shouldnt be trying to remove and fit props!
sorry for being so blunt but there we are. as for the others proposing all sorts of ways to do it, listen up.
A tapered shaft and prop should already be good enough to mate. make sure the tapers are clean and the key is in place and slide the prop on. put the locking washer on and then the nut, tighten up as hard as you can (assuming a 25mm shaft) with a socket and breaker bar. this will push the tapers together so that the prop taper expands and locks on to the shaft, tap the locking tab over and that is it. if you have a castellated nut then tighten it until one of the holes lines up and put the split pin in. If you have a cone anode put this on (it has nothing to do with keeping the prop on!!) and fill the hole behind the fixing screw wit some silicon to stop the screw falling out.
To take off, take off the anode, knock back the locking tab, undo the nut a few turns, and then get your 3 legged puller and put it on, tighten the puller as tight as you can and then twat the end of the puller jacking screw and the prop will jump off, it is now that you realise why we didnt take the nut off all the way, it stops the whole caboodle from falling on your toes!
The whole idea of the key and taper method is that the taper holds the bits together, the nut is just a device to make the connection and as a safety back up.
(in the olden days I used to work on diesel electric locos, the electric motor pinion which transmitted the 500 or so hp was actually a taper fit inside the shaft, it was fitted by using hydraulic pressure and then backed up with a 1" stud, the taper did all the work.
I suspect that your gori was being held on by just the taper!
Stu
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http://www.beneteau-owners-association.org.uk/toast/toast.asp
Edited by skipper_stu (02/06/2008 21:49)
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Tranona
regular
Reged: 10/11/2007
Posts: 1549
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With all due respects Stu, exactly what I said at the beginning of this thread. Interesting the two posters with a problem have not come back!
Probably a case of humble pie!
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neutronstar
regular
Reged: 09/09/2003
Posts: 54
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Well said Skipper-Stu.
The two issues I raised however, were directly related to the original post:
In probably half a dozen cases out of 100's over the past 40 years I have come across a prop that simply 'stripped' even the biggest claw puller. Probably age and over tightening in the first place caused the siezure. That is where the trusty multi studded monster I made gets the job done. Secondly I have come across a few more than a half a dozen cases where the Shaft & Prop tapers were not the same. Only maybe a thou or so out, but never the less that taper as you say 'should' do the work. If it does not the thing will probably work loose in time, even with the key and castleated split cotter fitted. A key that is loose in either keyway can also be considered unsafe. (and that happens a lot).
Another hard earned lesson I have picked up over the decades is to leave the puller on for a few hours and heat the prop core, occasionally squirting release gas on the joint. (and possibly water on the cutlass). Sometimes you walk away from it for a cup of tea and with an almighty bank the thing plops off.
As a consolation to the originator of this thread "the odd one in a hundred is an absolute swine".
Cheers
John
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CodStewart
regular
Reged: 11/01/2005
Posts: 823
Loc: Tashkent
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I came back. Just now. Thanks for the advice.
Hate to be thought badly of.
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www.ihaveaboat.blogspot.com "Only The Educated Is Free"
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highandry
regular
Reged: 17/02/2006
Posts: 368
Loc: South Coast UK
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Naughty..write 500 lines..."I must not bog off when the experts are in full flow" 
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Onyva
regular
Reged: 14/02/2005
Posts: 43
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Just got back from the boat -launched yesterday - and the prop is still on! Thanks for that Tranona, and thanks also to everyone else's too.
For the benefit of "sympathetic skipper Stu" the reason I AM messing around with props is that the YARD failed to get the prop off after several attempts over a 3 week period &, having tried everything else, suggested I cut it off - which I did very carefully with an angle grinder. My spare fixed prop fit perfectly & I used a locking washer, nut & cone anode (all blue loctited). That should do until we decide on a replacement folding prop.
Cheers & thanks for your help.
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Clifford_Pope
regular
Reged: 28/10/2005
Posts: 788
Loc: Pembrokeshire
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Ive just found this thread, which partly answers a question I wanted to put:
The boat has just been pulled out for the winter and I have noticed that the prop shaft nut is loose. It is castellated, and six months ago was wired on using thick galvanised wire, which has now corroded away.
Clearly that was the wrong method. Should I use a stainless steel cotter pin ? Or Monel, or bronze? The shaft is stainless, the prop and nut bronze.
If the tightest I can get the nut does not coincide with the single hole, should I use a longer lever, or back it off, or drill a new hole in the nut or shaft?
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Englander
regular
Reged: 07/09/2001
Posts: 15311
Loc: Barcelona/Bollyolics
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Tigten it up more!! Use a monel split pin. or 316 SS. Dont drill another hole, normally there are two holes, but you should be able to get it in line, if not remove nut, file a very wee bit off the back of the nut and refit, only do this if the holes are a small amount apart. If a long way, use a bronze washer/shim behind the nut.
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